New to stretching have questions

Ok so I recentally ordered the starter kit and as any guy on this forum I want to become bigger I’m around 7 right now but would like to break 8 and I was just wondering who has used these extenders and do they work I have read alot online and some people say that they work and others say that they don’t and most doctors don’t believe it

So who out there has used one and what kind of results have you seen I’m very nervous and excited to see if this will work I also have a big curve that I would like to get rid of that makes me appear shorter will this help correct this any tips help and pesonal expiernence would be greatly appreciated